Human organoids were derived from young (15–21 years old) and aged (>55 years old) patient stomach tissue collected from sleeve gastrectomies (IRB Protocol number 2015–4869) as previously described [16 (link)]. Briefly, stomachs were washed with DPBS, and mucosa was collected and cut into small fragments. Tissue fragments were incubated at 37°C supplemented with oxygen flow in DMEM/F12 with 1mg/mL Collagenase and 2mg/mL Bovine Serum Albumin. Glands were filtered and centrifuged at 65 × g for embedding into Matrigel. Human gastric organoid growth media was changed every 4 days (Advanced DMEM/F12 medium (Thermo fisher), 50% Wnt conditioned medium, 20% R-spondin conditioned medium, 1X Penicillin/Streptomycin, 1X Amphotericin/Gentamicin, 1X Kanamycin, 1X B27, 1X N2, 1mM N-Acetylcysteine, 10mM Nicotinamide, supplemented with growth factors including bone morphogenetic protein inhibitor, (Noggin, PeproTech), Gastrin I (Tocris), Epidermal grow factor (EGF, PeproTech), Y-27632 (Sigma), and Fibroblast growth factor 10 (FGF-10, PeproTech)) [16 (link)]. Human organoids were cultured at 37°C for 7 days prior to transplantation into NOD scid gamma (NSG) mice.